Released this week on DVD: "Examined Life"

Grade: B-minus

Examined Life is a lofty title -- it comes from Plato, we're reminded -- for a modest, intermittently engaging film. Astra Taylor, whose previous documentary feature, Zizek!, is the second-best film ever made about the Slovanian superstar Slavoj Zizek, here expands her frame of reference to include seven other prominent contemporary thinkers.

As a matter of academic training or departmental employment, not all are philosophers, strictly speaking, but they are all entertainers of big questions as well as earnest, often entertaining talkers. Part of the fun of Examined Life comes from watching these very intelligent people try to make themselves intelligible.

And the movie is fun, within certain limits. For some reason, Taylor has drawn her subjects from a narrow intellectual precinct, where the work of philosophical speculation and the agendas of progressive politics are assumed to be congruent. When Zizek utters the word "conservative" as a self-evident synonym for "unthinking" or "pernicious," he is giving voice to a shared, in some cases unexamined, notion that, as Karl Marx put it in his 11th Thesis on Feuerbach, the point is not to interpret the world, but to change it.

You would not know, judging from Examined Life alone, that other traditions and priorities exist. But this is the filmmaker's blind spot and should not necessarily be held against the professors who oblige her curiosity and try to answer her questions.

Taylor's contribution is to set these philosophers in motion, to transport them from the page and the seminar room into public spaces. Kwame Anthony Appiah of Princeton muses on cosmopolitanism in a departure lounge at the Toronto airport. Avital Ronnell, a literary theorist at New York University, strolls slowly around Tompkins Square Park in Lower Manhattan, while Martha Nussbaum, a law professor at the University of Chicago, strides purposefully along the edge of Lake Michigan.

Zizek, ever the showman, appears in an orange safety vest at a waste-disposal site, offering a contrarian critique of the way, in his view, the ecological movement idealizes nature. His harangue is amusing and occasionally provocative, except that rather than addressing the particulars of environmental politics, he is gleefully setting fire to a straw man of his own construction.

But the time at the dump with Zizek is more illuminating than 10 minutes in a rowboat with Michael Hardt, co-author of Empire, who muses on the incongruity of talking about revolutionary politics in Central Park, a place he characterizes as "aristocratic." Perhaps he is speaking in a highly specialized political idiom, according to which free public space designed by a onetime abolitionist and radical journalist somehow supports the prerogatives of inherited wealth and power. Or perhaps he's just not a very clear thinker.

But clarity is not always the chief virtue on display in Examined Life. Cornel West, the Princeton professor whose back-seat ramblings punctuate the film (everyone else has a single, uninterrupted minicolloquium), clearly takes great pleasure in talking, and it is hard not to share it, at least in small doses. A man of great, one might say compulsive, erudition -- not one to drop the name of a single great writer, composer or sage if five are available -- he makes the case that thought can be a kind of performance art.

And, indeed, Examined Life is less a tour of present-day philosophy than a study in academic celebrity. Taylor has offered each of her subjects the chance to show off a little, and they find ways of rising to the opportunity of subverting it. Some, like Zizek, Hardt and the Princeton ethicist Peter Singer, explicitly comment on their surroundings. Judith Butler, a gender theorist at the University of California-Berkeley, makes the act of taking a walk into an occasion for philosophical inquiry. Accompanied by the filmmaker's sister Sunaura Taylor, who uses a wheelchair because of a disability, Butler in effect transposes some of her difficult and subtle ideas about bodies, identity and social space into the language of everyday life.

More such examination would enliven Examined Life, which is on the whole a bit too glamorized by its brainy stars to engage them critically. Nor does it invite them to argue with one another, such contention, after all, being the real substance and practice of philosophy.

But Taylor does make some interesting introductions, and the sincerity of her admiration is not unwelcome, since nothing is easier than subjecting serious people to mockery. Which doesn't mean that they sometimes don't deserve it.